We propose a new method of sound ray tracing simulation to solve the problem variability of results due to the influence of the inputted level of detail of modeled rooms. This method offers a way to generate automatically room shapes suited to the analysis frequency. This method was verified by comparing with finite difference time domain method based on wave theory. As the result of a verification, it was clarified that the sound reflection angle can be mostly controlled by this method.

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The calculation model of radiative heat transfer considering directional characteristics of reflected solar radiation are introduced into 3D-CAD compatible outdoor thermal environment simulation, which authors have been developing. First, using method of separating isotropic diffuse reflection and specular reflection, directional characteristics of reflected solar radiation on the radiative heat transfer model are reproduced. Then, the calculation parameters are obtained from measurement result of the reflected directional characteristics of various materials by spectral radiometer. Finally, the effect of directional reflection of solar radiation on the outdoor surface temperatures is evaluated.

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In single-objective optimization problems, which have only one optimal design objective, the absolute optimal solution to maximize/minimize the objective function could be determined. However, in the most of real design problems, optimization problems become multi-objective, which two or more design objectives must be optimized simultaneously, and no single absolute optimal solution is existed. In these cases, recognizing what kind of alternative solutions exist in Pareto optimal sets seems to be useful for designers who have to decide an acceptable solution. In this paper, the authors carried out multi-objective optimization using multi-objective genetic algorithm through a case study involved in the real indoor environmental design-window design. Then the authors analyzed structure of Pareto optimal sets. Here we present the analysis process as well as the case study details, and show how the method proposed here is effective to decide an acceptable solution in multi-objective optimization problem.

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‘Crawl-space heating’ is a heating system using the crawl space as a duct for heat transport from a heat pump. The purpose of this study is to grasp the convective heat-transfer coefficient at the slab-concrete surface and the floor-under surface, under the condition of crawl-space heating. When the crawl-space heating is operated, the air velocity in the crawl space is generally 0.05-0.20m/s and the heat transfer is caused by both the forced convection and the natural convection. We measure the convective heat-transfer coefficient by the wind tunnel test. It is revealed that the convective heat-transfer coefficient at the slab-concrete surface is about 1.0-4.0W/m²K and that at the floor-under surface is about 6.0-10.0W/m²K.

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In order to evaluate the influences that differences in concrete strength have on hygrothermal behavior in walls, the water vapor permeability, equilibrium moisture content, hydraulic conductivity and thermal conductivity of concrete samples with three different strengths were measured. The following results were obtained:
The water vapor permeability and hydraulic conductivity tend to decrease with increasing strength. Movement of both the vapor and liquid phase occurs even at relatively low relative humidity.
Furthermore, a method of separating the moisture conductivities into the vapor and liquid phases was proposed and examined by making use of the measured results.

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It is recommended to set the room temperature at 20°C during winter for energy conservation. However, it is necessary to maintain the thermal comfort and health of occupants even under the low room temperature. Therefore, the individual adjustments by occupants will still require careful choice of clothing.
The present paper shows how residents would be dressed and perceive the temperature in a 20°C room, based on questionnaire survey, it investigates environmental and clothing conditions that provide thermal comfort in a 20°C room by conducting an experiment with human subjects and thermal manikin in chamber and computing the PMV and SET^*.

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The purpose of this study is to verify the effect on a sun-room for improving indoor climate of detached houses along the Pacific Coast of eastern Hokkaido. A convenient sun-room furnished with ‘insulated roof’ and ‘exposed ground’ was built in front of the south wall of a one-storied house that has two dwellings. We measured changes of temperature and humidity in the sun-room and two dwellings. In this report, the concepts to obtain thermal advantages by using the convenient sun-room were discussed through results of the measurement and simple unsteady numerical analyses. Stable environment for absolute humidity can be obtained by using humidity barrier and diatomite on the humidity barrier works to release moisture in the daytime. So from such results, it seems that a planning method of appropriate sun-rooms can be proposed for cool and foggy regions in summer.

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The effective radiation area and configuration factors for the human body are essential data to estimate the influence of thermal radiation upon the person in living environment. In this paper, the area and the factors between the man and rectangular planes, as the wall, ceilings or floors, for a male subject in his wheelchair were measured by the photographic method. The results showed that; (i) the effective radiation area of the human body was 0.82m² for the nude-condition, and 0.98m² for the clothing-condition, when his total body surface area was 1.75m²; (ii) the effective radiation area factor was 0.47 for nude, and 0.56 for clothing; (iii) the effective radiation area of the wheelchair was 0.42m²; (iv) diagrams of configuration factors between the human body and rectangular plane were represented; (v) diagrams of configuration factors between the wheelchair and rectangular plane were represented.

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In this study, we installed the odor sensors in patient room and clarified the variable factors affecting the level of odor. The level of odor changed when there were diaper changes, feeding tubes, patient repositioning, and cleanup, etc. And we compared the level of odor in the ordinary patient room with at the time of diaper change by odor measurement method by olfaction. There were some cases in which the odor concentration in the ordinary patient rooms and at the time of diaper changing were equivalent to 31. Patient rooms of the 32 year old building showed odor concentration as high as 230. However, about odor intensity, unpleasantness and acceptability, the level of odor of the diaper change patient room and the patient room of 32 year old building became high. It was suggested that the remaining odors were accumulated while repeatedly performing diaper changes with the door closed, therefore gradually raising the level of odor. The dilution ratio until threshold value of hydrogen sulfide and methyl mercaptane indicated about 20. These components are considered to influence sensory evaluation.

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In this study, we focus attention on odor of at the time of adult diaper exchange that was the factor to raise odor level in the patient room. An object of this study is to clarify main odor components and odor emission rate from excrement. In addition, we showed clearly the diffusion of the odors at the time of adult diaper exchange with the odor sensor installed in the patient room. The findings obtained are summarized as follows.
(1) Odor concentration of excrement changed with the amount of excrement, the treatment contents of the medication, the intake method of the meal and the kinds of the meal, etc. The highest odor concentration was 23000.
(2) The highest odor emission rate of at the adult diaper exchange was 460m³/min, and ventilation requirement was 57.5m³/min.
(3) We clarified the main components of excrement were “hydrogen sulfide”, “methyl mercaptan”, “isovaleric acid”, “n-valeric acid”, “butyric acid” and “aldehydes”.
(4) The odor generated at the time of adult diaper exchange diffused from the odor emission source, and the air current to occur by the work of the nurse influenced the diffusion of odor.

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Free cooling system is an energy saving system without chiller operation when the ambient temperature is relatively low and building needs the chilled water for cooling. The prediction method for free cooling performance is described in this paper with the theoretical formulae. The water temperature and the quantity of flow were measured in summer and winter in order to derive the parameters of the evaporative cooling tower. The predicted inlet and outlet water temperatures were agreed well with the measurement and it also shows the free cooling system with evaporative cooling tower may be available in Japan.

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In previous studies, it was difficult to evaluate the productivity only by task performance. In this study, we tried to evaluate productivity not only by task performance but also by human reaction, which especially meant fatigue. Fatigue was measured by subjective votes and biological signal, which were human voice and flicker value. It is said that the Lyapunov index of human voice has possibility to evaluate fatigue. The experiment was conducted under the condition of 800lx and 3lx to examine the effect of light environment on productivity. Subjects were fourteen. As a result of the experiment, we could not find a significant difference on task performance of addition task between 3lx and 800lx conditions. On the other hand, the increasing rate of symptoms from subjective votes was significantly higher on 3lx conditions than on 800lx, and a standard deviation of Lyapunov index of “g”, “p” increased more under 3lx than 800lx. There were significant differences on fatigue in the experiment.

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A subjective experiment was conducted to examine the influence of road traffic noise on productivity.
Multiplication task or short-term memorization task were assigned to thirty-two subjects in the indoor environment with only background noise (L_Aeq32dB) or with recorded road traffic noise (L_Aeq70dB). As a result, subjects evaluated the environment with road traffic noise as significantly unacceptable and discomfort compared to the environment with only background noise. From the correlation analysis, subjects who reported higher acceptability on the indoor environment tended to be less tired and were able to maintain higher concentration on task. The evaluation of indoor environment by occupants can be related to their state at work.

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The roof replanting system is excellent as the technology, which eases the global warming. Especially, Tokyo Metropolitan Government and Ministry of Land, Infrastructure and Transport Japan positively promote this system. In the meantime, next fact is necessary so that these may spread further. That is to say, the first is the security of the water source necessary for the plant. Then, the second are hygienic safety of the storage water quality in the roof, etc.
In this study, the water quality deterioration by the storage in making rainwater to be water source was measured, and the proper management technique was examined. To begin with, the Legionella was detected in 10⁴CFU/100mL order as a result of storing the rainwater for 4 months. From this result, disinfection examination by chlorination, ultraviolet disinfection method and ultraviolet ray and chlorination-combined use was carried out for the water quality of the storage tank. The disinfection examination result showed appropriate disinfection method of the Legionella done the survival in the water quality of the storage tank.

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Designing the morphology of urban districts (building clusters and roads) to maximize ventilation during summer is an effective way to mitigate the Urban Heat Island effect (UHI). Using wind speed, wind direction, and temperature measurements taken at pedestrian level in 2004 and 2005 in several central urban districts in Yokohama, Japan, this paper uses 6 original simplified 2 dimensional urban morphological parameters (A: angle between upper air flow and road; SHO: ratio of frontal aspect height to plan; CVR: ratio of roughness element horizontal length to plan; DNS: street canyon height difference; RW: road width; and TOSU: number of roughness elements) to analyze the link between urban thermal environments and the shape of roughness elements placed downstream in a regional air flow. In addition to smaller SHO, CVR, and TOSU values; as well as larger RW values, better ventilation (and hence less intense UHI conditions) was observed when A was closest to upper air flow direction; DNS was such that leeward building height exceeded that of windward buildings, and especially with lower values of SHO and CVR.

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In this paper, we carried out the field measurement in the urban district in Hiroshima City formed on the delta in Ohota River. We measured wind velocity and temperature in the sea wind in the summer. We showed the way of mitigation effect of high-temperature phenomenon of sea wind in the city. Results are as follows.
In the east and west street, the temperature lowers in street near coastline and river. In the north and south street, the temperature lowers around the coastline, and the temperature rises on the street which rises with entering the inland. In the place that the width of the holm is narrow and that the distance between rivers is short, the low temperature has been formed to the inside in the delta. This seems to be for supplying the cool air for the air flow in which air flow which goes up on the river ascends the street. Since the inflow of cool air flow is inhibited, in the holm which is the biggest commercial district tall building, the high-temperature range is formed. In the east and west street, the temperature tends to lower with the increase of the wind velocity in spite of the distance from the coastline. This seems to be because cool sea wind and which is not heated air flow on the river have the mitigation effect for the high-temperature of urban area.

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We conducted a survey on the daily cooling method such as opening windows or using air-conditioning or electric fan and ideal cooling method of the apartment buildings.
The main results are as follows: 1) as to ideal cooling method, more than 50% of occupants wanted to control temperature by opening windows or using electric fan, 2) the highest ratio of occupants who hated closing windows was in the morning, and the lowest ratio was during sleep, 3) many occupants wouldn't open windows at bedtime and during sleep, despite wanted to do so, 4) ideal cooling method changes according to time of day, and influences room temperature control.

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This study aims to find the diversity of people's evaluation on townscape, according to the attributes of participants using Caption Evaluation Method. Caption Evaluation Method was originally developed to evaluate the streetscape of a neighborhood high street individually, without limitations of the objective scenes and words used in the evaluation. In this study, the streetscape around an elementary school in the city center area is evaluated by the school children, neighborhood adults and architecture students who often visit this area as visitors (shoppers). Through the workshop, the differences are found among three groups.

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With a view to prevent global warming, to evaluate the reduction of environmental burdens of recycle-oriented, energy-saving housing which uses renewable energy, such as ground source (using heat pump), to provide space heating, cooling and domestic hot water, as well as utilizing dual purpose foundation piles for ground heat pump installation, a Life Cycle Assessment (LCA) can be used to quantify the beneficial effects on both the environment of utilizing these technologies. This paper shows LCA effects of different from the house equipment and structure.

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Although the population of Japan is going to decrease, the energy consumption of the residential sector is assumed to increase. On the other hand, new construction will decrease gradually, and the ratio of the existing houses in housing market will grow up. This research shows the prediction of CO₂ emission between 2005 and 2050 from housing sector of Fukuoka Prefecture by construction, operation, demolition and area based on the present situation of the housing stock.
Fukuoka Prefecture is divided into “Fukuoka City”, “Kitakyushu City” and “The other area”. The trend CO₂ emission and the main factor are different by areas, directly because the decrease of population and the change of household composition. Accordingly the effect of the measures would change. In Fukuoka City CO₂ emission has a high percentage of the construction and operation factor on apartment house, therefore it is said that the measures for the apartment house are comparatively important. Meanwhile in Kitakyushu City and The other area, new construction of detached house has a large percentage in new construction, but taken altogether, it is a small amount. The measures for the housing stock are important.

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